High density connectors are well known in the electronic industry as well as the automotive industry. In both industries the need for complex electrical connections must be married with an ever increasing need for the minimization of the size and weight of all parts. These needs have lead to the development of high density connectors. High density connectors provide a large number of individual electrical connections located within reduced size connector components. Although developments in high density connectors have lead to known improvements in connector density, minimization of their size has been limited by the ability to attach such connectors to the circuit boards to which they provide electrical communication.
Each individual electrical connection within a high density connector must be provided with a unique electrical path to the circuit board. Known methods of providing such pathways, such as solder connections, often create limitations on the layout and size of the high density connector. The electrical pathways created by solder and other conventional methods require surface areas that are known to prevent the individual connections within the high density connector from being placed too close to one another. A method of connection, however, is known that utilizes very thin connections to create pathways between a high density connector and a circuit board. This method is known as wirebonding. The electrical pathways created by wirebonding have small cross-sectional areas and may be placed within close proximity to each other. These characteristics make wirebonding highly suitable for use with high density connectors.
Although the scale of individual wirebonds make them naturally suitable for use with high density connectors, they have additional characteristics that have served to limit their use and have restricted the size and density of high density connectors employing them. The thin arcs of metal created by wirebonding become fragile when the distance between connection points becomes either too great or the arcs cover too great a vertical distance. This characteristic limits the use of wirebonding in applications that may be exposed to vibrations. Applications within industries such as the automotive industry often require their electrical components to survive environments with vibrational characteristics that prevent the use of such long wirebonds.
It is known that to circumvent the vibrational deficiencies of long wirebonds the high density connectors used in such environments may be limited to two rows of pins within the connector. Although this limits the length of the wirebonds, it requires longer connectors to accommodate a given number of electrical connections. Since size and density of such connectors is often a primary characteristic, such solutions are undesirable. High density connectors with three and four rows of connections often require pathways to the circuit boards on both sides of the high density connector. This limits the size and design flexibility of such connectors making such solutions undesirable for many applications.
Another method of compensating for the lack of vibrational resiliency in wirebonds is through the use of complex connector designs. One common connector design uses pin elements within the high density connector. A clear pathway from the ends of these pins to the circuit board must exist to create the wirebond. To accommodate these pathways the geometry and size of the multi-row connectors are restrained. One known method to accommodate such pathways utilizes staggered spacing between rows of connectors. This is undesirable since it requires a greater area for a given number of connections. Another known method places the connection points on surfaces 90 degrees to each other. While this decreases the length of the wirebonds, it increases their vertical distance and therefore can have undesirable vibrational characteristics. In addition, the high density connectors used in this method can be costly and difficult to manufacture.
Therefore, there is a need for a high density connector that can utilize the positive characteristics of wirebonding to create a highly dense connection pattern, while eliminating the poor vibrational characteristics, size limitations, and manufacturing costs associated with known designs.